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Chemical evaluation of the quality of nanostructures synthesized on the surface of indium phosphide

Kovachov S. S., Bogdanov I. T., Pimenov D. O., Bondarenko V. V., Konovalenko A. A., Skurska M. M., Konovalenko I. S., Suchikova Y. O.

Archives of Materials Science and Engineering

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2021

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Vol. 110, nr 1

18--26

EN

Purpose: The article proposes a methodology for determining the chemical quality criterion of porous layers synthesized on the surface of semiconductors, based on taking into account the chemical parameters of the surface that can affect the properties of nanostructures. Design/methodology/approach: The chemical quality criterion was evaluated in terms of stoichiometry, stability of structures over time, uniformity of distribution over the surface, and the presence of an oxide phase. As an example, a calculation is demonstrated for the por-InP/InP structure synthesized on a mono-InP surface. The results of calculating the chemical quality criterion were evaluated using the Harrington scale to rank samples by quality level. Findings: A chemical criterion for the quality of porous layers synthesized on the surface of semiconductors has been developed. This criterion contains a set of indicators sufficient for a comprehensive assessment of the surface condition and is universal in nature. The studies carried out make it possible to reasonably approach the determination of the modes of electrochemical processing of semiconductors and open up new perspectives in the construction of a model of self-organization of a porous structure. Research limitations/implications: The chemical quality criterion does not allow evaluating the obtained nanostructures in terms of geometric parameters. Therefore, in the future, there is a need to develop a morphological quality criterion and determine a methodology for assessing a generalized quality criterion for nanostructures synthesized on the surface of semiconductors, which may include economic, environmental, technological indicators, and the like. Practical implications: Study results are expedient from a practical point of view, since they make it possible to reasonably approach the determination of the modes of electrochemical processing of semiconductors, synthesize nanostructures with predetermined properties, and create standard samples of nanomaterial composition. Originality/value: Methodology for assessing the quality of porous semiconductors by a chemical criterion has been applied for the first time in engineering science. The article will be useful to engineers, who are engaged in the synthesis of nanostructures, researchers and scientists, as well as specialists in nanometrology.

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Oxide crystals on the surface of porous indium phosphide

Suchikova Y. O., Bogdanov I. T., Kovachov S. S.

Archives of Materials Science and Engineering

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2019

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Vol. 98, nr 2

49--56

EN

Purpose: f this paper is to is to establish the patterns of oxide formation on the surface of indium phosphide during electrochemical etching of mono-InP. Design/methodology/approach: A porous surface was formed with the anode electrolytic etching. Morphology of the surface was studied with the help of scanning electron microscope JSM-6490. The analysis of chemical composition of porous surface of samples was also performed. Findings: It was shown that during the electrochemical etching of indium phosphide, oxide films and crystallites form on the surface. It has been established that crystalline oxides are formed mainly on the surface of n-type indium phosphide. Continuous oxide films are predominantly formed on the surface of p-InP. Research limitations/implications: The research was carried out for indium phosphide samples synthesized in the solution of hydrofluoric acid, though, carrying out of similar experiments for crystalline oxides on the surface of porous indium phosphide obtained in other conditions, is necessary. Practical implications: The study of oxide crystals on the surface of porous indium phosphide has great practical importance since it is the reproducibility of experimental results that is the main problem of modern materials science, the more nanoengineering. Oxides can significantly affect the properties of materials. On the one hand, oxides significantly affect the recombination properties of materials, this can impair the operation of semiconductor devices. On the other hand, oxide films can serve as a passivating coating for the surface of a porous semiconductor. Such an oxide property will be useful for the practical application of nanostructured indium phosphide. Therefore, questions of the conditions for the formation of semiconductor intrinsic oxides, their structure, and chemical composition, and also the effect of oxides on the physical and technical characteristics of materials are important. Originality/value: The patterns of oxide formation on the surface of indium phosphide during electrochemical etching are investigated in this work. It is shown for the first time that the structure of an oxide depends on the orientation of the surface of the semiconductor. It was shown that continuous oxide films are formed on the surface of p-InP, and oxide crystalline clusters are formed on the surface of n-InP.

3

Photonic integrated circuits - a new approach to laser technology

Piramidowicz R., Stopiński S., Ławniczuk K., Welikow K., Szczepański P., Leijtens X., Smit M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2012

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Vol. 60, nr 4

683-689

EN

In this work a brief review on photonic integrated circuits (PICs) is presented with a specific focus on integrated lasers and amplifiers. The work presents the history of development of the integration technology in photonics and its comparison to microelectronics. The major part of the review is focused on InP-based photonic integrated circuits, with a short description of the potential of the silicon technology. A completely new way of fabrication of PICs, called generic integration technology, is presented and discussed. The basic assumption of this approach is the very same as in the case of electronic circuits and states that a limited set of standard components, both active and passive, enables designing of a complex, multifunctional PIC of every type. As a result, functionally advanced, compact, energy efficient and cost-optimized photonic devices can be fabricated. The work presents also selected examples of active PICs like multiwavelength laser sources, discretely tunable lasers, WDM transmitters, ring lasers etc.

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High-sensitivity NO2 sensor based on n-type InP epitaxial layers

Wierzbowska K., Adamowicz B., Mazet L., Brunet J., Pauly A., Bideux L., Varenne C., Berry L., Germain J. P.

Optica Applicata

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2005

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Vol. 35, nr 3

655-662

EN

The structure and sensing properties of a novel resistive NO2 sensor based on n-type InP epitaxial layers have been presented. The studies of sensor resistance changes due to adsorbed gas NO2 under exposures in the range from 20 to 100 ppb at a temperature of 80°C were performed. The thickness of the active InP layer changed from 0.2 to 0.4 um. The response time and signal stability were also investigated. Furthermore, the influence of surface states and near-surface region on sensor parameters in terms of the resistance relative changes was shown from numerical simulations. The analysis of the measured photoelectron spectroscopy (XPS) spectra confirmed the complex chemical composition of the InP oxides, which gives rise to the high density of surface states.